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    La

    Lanthanum

    Lanthanide

    Atomic Number: 57 • Atomic Mass: 138.9100 u • Period: 6 • Group: 3

    Electron Configuration: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 5d¹
    Phase: Solid
    Electronegativity: 1.1
    Barium (Ba)Cerium (Ce)
    OverviewPropertiesAtomic StructureOccurrenceApplicationsHistory

    Overview

    Lanthanum is the chemical element with the symbol La and atomic number 57. It belongs to the Lanthanide group and is located in period 6 of the periodic table. It exists as a solid under standard conditions.

    Basic Information

    • Symbol:La
    • Atomic Number:57
    • Atomic Mass:138.9100 u
    • Group:3
    • Period:6
    • Category:Lanthanide
    • Phase at STP:Solid
    • Electronegativity:1.1 (Pauling scale)

    Key Facts

    Fun Fact #1

    Name comes from Greek 'lanthanein' meaning 'to lie hidden'

    Fun Fact #2

    First lanthanide discovered

    Common Uses

    • Hybrid car batteries
    • Camera lenses
    • Carbon arc lighting